An image forming apparatus includes: a nozzle head in which nozzles that ejects ink is arranged in a first direction; a moving mechanism that moves a recording medium relative to the nozzle head; an image acquirer that acquires image data; a quantization processor that quantizes density of pixels forming an image based on the image data; a grouping processor that groups adjacent pixel positions into one group in the quantized data; and a rearrangement processor that rearranges a quantized pixel value at each pixel position in the group that is grouped, wherein the grouping processor groups such that a direction intersecting the first direction is set to a second direction, arrangement of groups in the first direction is set to a row, rows is arranged in the second direction, and a row in which an initial position of the row is different at least by one pixel is included.

A printing apparatus includes a print execution section and a controller. The print execution section includes: a printing head having nozzles arranged in a first direction; a head driver that drives the printing head to discharge ink from the nozzles thereby forming dots on a printing medium; and a movement mechanism that moves the printing medium relative to the printing head in any of the first direction and a second direction intersecting with the first direction. The controller obtains a piece of object image data, generates, by using the object image data, a plurality of pieces of dot data indicating formation states of the dots for pixels, and prints a printing image by causing the print execution section to execute discharge of the ink and movement of the printing medium by use of the pieces of dot data.

An object is to print a high quality image with resistance to print misalignment. To this end, the image processing apparatus generates quantized data for printing a first dot pattern and a second dot pattern in an overlapping manner. The first dot pattern and the second dot pattern are lattice patterns varying in a combination of two basis vectors. In a combined dot pattern obtained by combining the first and second dot patterns, there is a neighboring dot in which a dot in the first dot pattern and a dot in the second dot pattern are arranged at an interval smaller than a lattice spacing. The neighboring dot includes multiple neighboring dots varying in an approach direction.

A technique includes printing a first image including a plurality of edge pixels and a second image with a lower ratio of edges pixels than the first image and an average density equal to that of the first image and determining a value of a processing parameter so that the average densities of the first image and the second image match. The technique is configured to realize appropriate pre-print processing while preventing the average densities from being low due to the excessive pre-print processing or being high due to the insufficient pre-print processing.

The disclosed embodiments include a method to compensate for defective printer nozzles. The method can include detecting a defective printer nozzle and initiating a print job including image data of the defective printer nozzle for a pixel location of an image. The image is to be printed in accordance with a print mask that maps printer nozzles to pixel locations of the image. The method can include modifying the image to print the image data in a neighboring pixel location relative to the pixel location of the image and printing the modified image.

A printing apparatus comprising a printing head including a plurality of nozzles, a correction value setting unit configured to set a correction value, a printing data generation unit configured to correct image data and a printing control unit configured to cause to print a first region and a second region on, based on the image data after correction, wherein the printing control unit causes to print one of the first raster lines with a predetermined number of the nozzles and to print one second raster line with a number, greater than the predetermined number, of the nozzles, and the correction value setting unit sets the correction value applied to the second raster line and the correction value applied to some of the first raster lines, in accordance with a printing condition that changes a concentration difference of the second raster line from the first raster lines.

An image processing apparatus that generates image data to be output to an image forming apparatus printing an image, and includes: a generation unit configured to generate, based on an input image, first generation amount data indicating a generation amount of each of one or more kinds of ink dot for each pixel and second generation amount data indicating a generation amount of a blank dot for which the ink dot is not formed for each pixel; and a processing unit configured to determine a dot arrangement pattern indicating an arrangement of each of the one or more kinds of ink dot by performing quantization processing using the first generation amount data and the second generation amount data.

A printing system is provided comprising a print head including a plurality of ink nozzles; an actuator configured to move the print head relative to a substrate; a print head position sensing system configured to detect an actual position of the print head relative to the substrate; and a controller. The controller is configured to: receive the actual position of the print head detected by the print head position sensing system corresponding to a target print head position; determine a positional offset between the actual position and the target print head position; generate a nozzle firing pattern based on the positional offset; and control the print head to print the nozzle firing pattern at the target print head position using the plurality of ink nozzles.

There is provided a printer including: a printing part having: a conveyor configured to convey a medium in a conveying direction; a printing head having a plurality of nozzles from which an ink of a specified color is discharged and of which positions in the conveying direction are mutually different, the printing head being configured to discharge the ink from the plurality of nozzles to the medium so as to form dots in the medium; and a facing member configured to be capable of facing a print surface of the medium on an upstream side in the conveying direction with respect to the plurality of nozzles of the printing head; and a controller.

An image forming apparatus includes: a nozzle head in which nozzles that ejects ink is arranged in a first direction; a moving mechanism that moves a recording medium relative to the nozzle head; an image acquirer that acquires image data; a quantization processor that quantizes density of pixels forming an image based on the image data; a grouping processor that groups adjacent pixel positions into one group in the quantized data; and a rearrangement processor that rearranges a quantized pixel value at each pixel position in the group that is grouped, wherein the grouping processor groups such that a direction intersecting the first direction is set to a second direction, arrangement of groups in the first direction is set to a row, rows is arranged in the second direction, and a row in which an initial position of the row is different at least by one pixel is included.